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Re: ANSI Standard for 14x17 holder seems odd

Randy, I'm the guilty party in at least some of these instances. It's not all wrong; there are only a few obvious errors. It is also less complete than the fairly up-to-date information that Greg Davis posted above. Greg's information is identical with the same specification I got directly from ANSI a few years ago, and with minor exceptions from the 1951 specifications in The Camera Repairman's Handbook. The older specification differed by including the 1/4" additions to 2x3 and 3x4 film sizes. The 1998 version adds the "J" dimension for the thickness of the septum in only the 11x14 and 14x17 holders, film sizes that the 1951 version did not cover.

Here is a reply to an earlier posting of Randy's link:
It should be noted that some of the information in this often cited illustration may be questionable. The depth to film surface distance (the "T" distance) as shown in my 1951 copy of the ASA standards is to the back, not the front, of the film. The Exposure Height measurement given is apparently the ASA D2, not the appropriate D3, measurement. The Exposure Width measurement is the E1 maximum, not the appropriate E3 measurement. The Retaining Tab Location is a maximum; the minimum is .010" less. The Length dimension is a minimum: ASA specified no maximum. The Width is a maximum: the minimum is about .031" less. The Distance to Exposure Field is a maximum: the minimum is .020 less for up through 5x7 holders and .030 less for 8x10 holders. I don't have ASA information on holders larger than 8x10. Dimensions in newer versions of the ASA or ANSI standards may differ.

At least the provider of the information Randy cited tried to be of service without violating copyright laws. Now that we are on the path to assembling comprehensive and accurate information, we should lay that citation to rest. This will be an ongoing process, and eventually should encompass the variations with which different photo equipment makers have plagued us for so long.

Re: ANSI Standard for 14x17 holder seems odd

Originally Posted by Jim Jones

At least the provider of the information Randy cited tried to be of service without violating copyright laws. Now that we are on the path to assembling comprehensive and accurate information, we should lay that citation to rest. This will be an ongoing process, and eventually should encompass the variations with which different photo equipment makers have plagued us for so long.

I really appreciate all the information that this thread has provided. The internet is full of answers, but this was one of those times when one of the most referenced sources of information (and not just by Randy!) seemed incorrect. That it is only partially incorrect made me, an inexperienced newcomer to all this, suspect that it was me who was wrong.

Since I'm actually going to use this information to make tangible things that I'll need to cut out of real wood and other stuff*, I'm going to print out the pages that GregDavis provided (thanks very much for that!). I tend to lose things that float around in my laptops, or my laptops do. People say that things online last forever, but I sure have not found that to be true. If there was some kind of average lifespan, that would be great, but too often I've gone looking for something fairly recent, only to get a 404 message. It might be a while (months to a year) before I get to the cutting. I don't want to lose this!

*I did get the mini mill I mentioned up-thread, and needed to completely rearrange my workshop in order to find a good place for it. The only times I was able to get out there coincided with sub-zero temperatures and strong winds. My workshop is insulated and heated, but not very well, so the work has been pretty slow and not very pleasant -- and long overdue! It's not quite done yet, either, so it will be while before I do some actual building on the camera. I was also right about buying tooling for the mill. I've no experience with machining, but now have most of the needed tools, several books, and a bunch of videos to get me going. The camera project has actually fallen far back in the queue of Stuff to Do. But I see that as a good thing. This is all fascinating and fun!

Re: ANSI Standard for 14x17 holder seems odd

Originally Posted by GregDavis

Hi Everyone
I tried to buy the ANSI standard for film holders from official source but they would not provide it to me, as it has been withdrawn. I then sourced it from a less official Asian source, but still had to pay for it!

So now for the good of the photographic community, attached are the 4 most relevant pages of the ANSI IT3-108-1998 standard. The other pages are front cover, index, introduction, forward which are not technical.

Very helpfull of you to post this .
I'm about to make a couple of cameras or adapt one other to use a larger format that was intended , and having this information to make a ground glass holder makes it easier to stick with standard gear like DDS if I can obtain some ( at the right price ) .

Re: ANSI Standard for 14x17 holder seems odd

Excellent! Another source to work with. This whole thread will be a great place for folks to come and find what they need for DIY.

I've gotten stalled on my actual camera build. It was only last week that I finally got my mini-mill tweaked to the point where I feel confident in its stability and tramming. That's been a fun project in itself, but so far, the only milling I've done is of parts for the mill. The time and money I've spent on measuring devices, tooling, practicing, and such has left me much more knowledgeable, but bereft of funds for the materials I need to actually build the camera. I need to regroup, buy some items to fix and sell (my source of income for my hobbies), and then continue.

I have gotten some stuff for the camera, including two lenses: a 19-inch Apo Artar and a 760mm Apo Ronar CL. I know that buying the lenses before having the camera might seem like a backwards thing to do, but I keep my eye out for deals, and found these two too good to pass up. $45 for the Artar, and $200 for the Ronar, which also came with a 240mm companion, both mounted on the same process camera board. I plan to sell the 240mm to recoup some of the cost of the 760. All the lenses came cheap because each was quite dirty. The Artar cleaned up nicely, but I have not messed with the others yet. None are in shutters, and I know I can probably do without, but I have some ideas.

By the way, though this is quite off-topic, since I brought up the Ronars, can anyone explain some writing on the aperture scales on the board? On the scale for the 240, it says 'Apo Ronar CL 240-800', and on the other scale it says, 'Apo Ronar CL 760-1200'. What do the 800 and 1200 signify?

Re: ANSI Standard for 14x17 holder seems odd

I am very confused about the lenghts of the film holder and the position of the retaining tab. The length (A) is 497mm and the position of the retaining tab is 490mm. So that leaves 7mm for the rest of the filmholder? Around 475mm seems more appropriate to me for the location of the retaining tab. Can anyone explain to me what I am missing?

Re: ANSI Standard for 14x17 holder seems odd

Originally Posted by Renze

I am very confused about the lenghts of the film holder and the position of the retaining tab. The length (A) is 497mm and the position of the retaining tab is 490mm. So that leaves 7mm for the rest of the filmholder? Around 475mm seems more appropriate to me for the location of the retaining tab. Can anyone explain to me what I am missing?

This is simply because A is defined as A min, e. g. minimum length for A. In practise you could make your holder as long as you want to.